Jumbo has completed the transport and handling of offshore wind turbine foundation components for Orsted’s 1400MW Hornsea 2 offshore wind farm in the UK North Sea.
The Dutch offshore contractor deployed its K-3000 class heavy lift vessel Fairmaster to carry out its scope of transporting 141 monopiles and 131 transition pieces from Rostock, Germany and Aalborg, Denmark to Eemshaven in the Netherlands.
This was the largest amount of monopiles and transition pieces that the company has ever shipped in a single contract as well as the most it has carried with a single heavy lift vessel.
The monopiles themselves were 8.5 to 9.5 metres in diameter and weighed up to 1285 tonnes.
Jumbo’s 152.9 metre long Fairmaster vessel, which has two 1500 tonne cranes, was able to provide a flexible deck layout that assisted in the project’s timing schedule.
Jumbo project manager Maarten De Gruyter said: “This engineered flexible solution made it an extremely efficient vessel for the project and is one of the things we’re most proud of – it helped us conclude the project scope within just 37 voyages in a period of just under twelve months.
“We had close cooperation with DEME Offshore with regards to scheduling, and we could handle many changes to the sailing sequence.
“Ultimately, this meant that we could carry more equipment within less time.
“During the planning phase, we designed and engineered the MP saddles and TP grillages to deliver our proposed vessel efficiency.”
The company said it used inlays in the saddles to accommodate the different diameters of the monopiles and it also installed project-specific lifting lugs on the deck hatches to speed up loading and unloading operations.
As part of reducing the environmental footprint of the construction of the Hornsea Two offshore wind farm, Jumbo was required to include a Green Initiative into its project execution, for which the company chose to sail with biofuel oil from sustainable marine biofuel provider GoodFuels.
Jumbo commercial manager Boudewijn van der Garden said: “We converted the Fairmaster into a kind of ‘Swiss Army knife’ that provided an unrivalled heavy lift vessel intake of large diameter monopiles and transition pieces, but still with the flexibility required for the various lengths and diameters that were to be transported.
“From tender to project conclusion, Jumbo’s focus was to provide a total solution. Our office personnel, engineering teams and vessel crews are now ready for the next challenge.”